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An all-epitaxial approach was demonstrated to create coaxial plasmon laser structures composed of an aluminum plasmonic metal/SiNx dielectric/InGaN quantum well shell surrounding a p-GaN nanowire core. Strong UV luminescence was observed from as-grown vertically-aligned arrays as well as horizontally-aligned nanowires transferred to a transparent carrier wafer. (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

This article presents the use of flexible carbon substrates for the growth of III-nitride nanowire light emitters. A dense packing of gallium nitride nanowires were grown on a carbon paper substrate. The nanowires grew predominantly along the a-plane direction, normal to the local surface of the carbon paper. Strong photo- and electro-luminescence was observed from InGaN quantum well light emitting diode nanowires. (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

In preparing periodically-oriented gallium nitride (PO GaN) samples for optical applications, smooth surfaces are essential. Although post-growth processing of these surfaces is possible, it is challenged by significantly different reactivity of the two polar surfaces. To this end, it would be highly desirable to grow PO GaN structures with smooth surfaces. In this paper, the influence of growth parameters on the morphology of PO GaN structures is investigated. The three primary parameters investigated include the V/III ratio of the gas phase precursors, the nature of the carrier gas, and the geometry of the structure. The V/III ratio was varied from 1100 to 5500. Substitution of N2 for the standard H2 carrier gas is investigated. Finally, the effects of changing the structure periodicity from 2 to 100 mm are studied. Smoother structures (resulting from more equal growth rates of the two polarities) are achieved with increases in V/III ratio, substitution of H2 with N2, and by reducing the stripe width. (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Memtransistors: Programmable Multilevel Memtransistors Based on van der Waals Heterostructures (Adv. In article number 1900333, Jihyun Kim and co-workers demonstrate a programmable memtransistor architecture based on van der Waals heterostructure with high computing functionality. These memtransistors, monolithically integrating a 2D memristor with a 2D transistor, exhibit a programmable multi-state computing window with a tunable current on/off ratio. [Extracted from the article]

Neuromorphic computing that mimics the energy‐efficient cortical neural network in the human brain is attractive because of its possibility to process complex and massive data sets and achieve fast computing capability. Herein, a heterosynaptic and programmable memtransistor architecture with high computing functionality is reported by monolithically integrating a hexagonal boron nitride (h‐BN) memristor with a molybdenum disulfide (MoS2) transistor. Memristors consisting of a vertically stacked van der Waals materials (multilayer graphene (MLG) and h‐BN) exhibit a stable bipolar resistive switching behavior with a memory window more than three orders of magnitude due to the formation and rupture of the metallic filament within the h‐BN layer. By controlling the resistance state of the h‐BN memristor, the behaviors of the memtransistor can be programmed with a high switching ratio of ≈104, showing ≈16 pW standby power consumption. A multistate computing window and tunable current on/off ratio can be achieved by controlling the synaptic weight of the memristor, demonstrating that the presented 2D architecture can be exploited as a logic inverter device. The results pave the way toward the development of highly functional neuromorphic systems for the next‐generation in‐memory computing. [ABSTRACT FROM AUTHOR]